CA1205556A - Grid antenna - Google Patents
Grid antennaInfo
- Publication number
- CA1205556A CA1205556A CA000446113A CA446113A CA1205556A CA 1205556 A CA1205556 A CA 1205556A CA 000446113 A CA000446113 A CA 000446113A CA 446113 A CA446113 A CA 446113A CA 1205556 A CA1205556 A CA 1205556A
- Authority
- CA
- Canada
- Prior art keywords
- feed
- antenna
- grid
- parabolic antenna
- axis
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
- H01Q15/14—Reflecting surfaces; Equivalent structures
- H01Q15/16—Reflecting surfaces; Equivalent structures curved in two dimensions, e.g. paraboloidal
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
- H01Q19/10—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces
- H01Q19/12—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces wherein the surfaces are concave
- H01Q19/13—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces wherein the surfaces are concave the primary radiating source being a single radiating element, e.g. a dipole, a slot, a waveguide termination
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Aerials With Secondary Devices (AREA)
Abstract
GRID ANTENNA
Inventor: Donald W. Matz, Jr.
ABSTRACT OF THE DISCLOSURE
A grid parabolic antenna formed of a peripheral hoop and a plurality of metallic reflector ribs arranged in planes substantially parallel to each other and connected to the hoop. The reflector ribs each have an elongated cross-sectional configuration, with the elongation being in a direction that is generally parallel to the axis of the antenna feed which is at the focus of the parabola.
Inventor: Donald W. Matz, Jr.
ABSTRACT OF THE DISCLOSURE
A grid parabolic antenna formed of a peripheral hoop and a plurality of metallic reflector ribs arranged in planes substantially parallel to each other and connected to the hoop. The reflector ribs each have an elongated cross-sectional configuration, with the elongation being in a direction that is generally parallel to the axis of the antenna feed which is at the focus of the parabola.
Description
BACKGROUND OF THE INVENLlu-~
The present invention concerns a novel grid parabolic antenna which is constructed in a manner for reducing the amount of back radiation.
In U.S. Patent No. 2,850,735, a grid parabolic antenna is disclosed in which a number of spaced parallel aluminum tubular reflector ribs are contoured and their ends are connected to a peripheral hoop to form a parabolic antenna structure. A primary advantage of the gr~d type parabolic antenna over a solid parabolic antenna is that the grid antenna has wind loading characteristics of only 20 percent to 40 percent of comparable si~e solid parabolas.
Both grid type parabolic antennas and solid parabolic antennas have leakage around the antenna thereby resulting in a certain amount of side and back radiation. During transmission, the side and back radiation may cause inter-ference with other signals which are being fed in the same direction from other antennas. It has been found that prior art grid antennas, such as illustrated in U.S. Patent No.
The present invention concerns a novel grid parabolic antenna which is constructed in a manner for reducing the amount of back radiation.
In U.S. Patent No. 2,850,735, a grid parabolic antenna is disclosed in which a number of spaced parallel aluminum tubular reflector ribs are contoured and their ends are connected to a peripheral hoop to form a parabolic antenna structure. A primary advantage of the gr~d type parabolic antenna over a solid parabolic antenna is that the grid antenna has wind loading characteristics of only 20 percent to 40 percent of comparable si~e solid parabolas.
Both grid type parabolic antennas and solid parabolic antennas have leakage around the antenna thereby resulting in a certain amount of side and back radiation. During transmission, the side and back radiation may cause inter-ference with other signals which are being fed in the same direction from other antennas. It has been found that prior art grid antennas, such as illustrated in U.S. Patent No.
2,850,735, have substantially more back radiation than solid antennas, However, the low wind loading characteristics of the grid antennas makes the use of the grid antennas necessary under many conditions.
FCC Part 9~ includes a category A requirement which specifies a maximum amount of side and back radiation that is permitted with respect to parabolic antennas. In the 2100-2300 megahert~ band, a conventional six-foot solid parabolic antenna complies with the category A requirement, but the conventional six-foot grid type parabolic antenna does not comply with the category A requirement. Therefore, _ ) _ ~lZ~SSS6 it has ~een believed that a si~-foot grid type parabolic antenna could not be used in the 2100-2300 megahertz band where FCC Part 94 category A is applicable. However, I have discovered a novel construction for reducing significantly the back radiation of a grid antenna.
Therefore, it is an object of the present invention to provide a grid antenna having less ~7ind resistance than a solid antenna but also having less back radiation than the back radiation provided by prior art grid antennas.
A further object of the present invention is to provide a grid antenna which has substantially no more back radiation than the back radiation of a solid antenna of the same size.
Another object of the present invention .is to provide a grid antenna that has reduced back radiation and that is relatively simple in construction and Lelatively easy to manufacture.
Other objects and advantages of the present inven-tion will become apparent as the description proceeds.
SUMMARY OF THE INVENTION
In accordance with the present invention, a grid parabolic antenna is provided of the type formed of a peripheral hoop and a plurality of spaced metallic reflector ribs having a parabolic contour, with the reflector ribs being arranged in planes substantially parallel to each other and connected to the hoop, and with an antenna feed at the focus of the parabola. The improvement comprises the cw~ 3 -95~56 reflector ribs each comprising a plurality of connected circular tubes and having an elongated cross-sectional configura~ion, with the elongation being in a direction generally parall.el to the axis of the feed.
cwt ~ - 3a -,'`
~ ~5556 In one embodiment of the invention, the reflector ribs each comprise a plurality of connected circular tubes.
In another embodiment of the invention, the reflector ribs each comprise a tubular conductive member with the cross-sectional configuration of the tube having a major axis in a direction generally parallel to the axis of the feed and having a minor axis generally perpendicular to the major axis. In one form of this embodiment, the reflector ribs each comprise a tubular conductive member having a generally rectangular cross-sectional configuration.
In the illustrative embodiment, the feed includes passive means for providing a relatively rectangular primary beam. The passive means comprise a secondary member carried by the feed for providing a phase shift to shape the primary beam so that it is relatively rectangular A more detailed explanation of the invention is provided in the following description and claims, and is illustrated in the aceompanying drawings.
BRIEF DESCRIPTION OF ThE DGAWlNGS
FIGURE 1 is a perspeetive view of a grid parabolie antenna eonstrueted in aeeordanee with the prineiples of the present invention;
FIGURE 2 is a eross-seetional view thereof, taken along the plane of the line 2-2 of FIGURE l;
FIGURE 3 is an enlarged, broken eross-seetional view, taken along the plane of the line 3-3 of FIGURE 2;
FIGURE 4 is a eross-seetional view similar to FIGURE
FCC Part 9~ includes a category A requirement which specifies a maximum amount of side and back radiation that is permitted with respect to parabolic antennas. In the 2100-2300 megahert~ band, a conventional six-foot solid parabolic antenna complies with the category A requirement, but the conventional six-foot grid type parabolic antenna does not comply with the category A requirement. Therefore, _ ) _ ~lZ~SSS6 it has ~een believed that a si~-foot grid type parabolic antenna could not be used in the 2100-2300 megahertz band where FCC Part 94 category A is applicable. However, I have discovered a novel construction for reducing significantly the back radiation of a grid antenna.
Therefore, it is an object of the present invention to provide a grid antenna having less ~7ind resistance than a solid antenna but also having less back radiation than the back radiation provided by prior art grid antennas.
A further object of the present invention is to provide a grid antenna which has substantially no more back radiation than the back radiation of a solid antenna of the same size.
Another object of the present invention .is to provide a grid antenna that has reduced back radiation and that is relatively simple in construction and Lelatively easy to manufacture.
Other objects and advantages of the present inven-tion will become apparent as the description proceeds.
SUMMARY OF THE INVENTION
In accordance with the present invention, a grid parabolic antenna is provided of the type formed of a peripheral hoop and a plurality of spaced metallic reflector ribs having a parabolic contour, with the reflector ribs being arranged in planes substantially parallel to each other and connected to the hoop, and with an antenna feed at the focus of the parabola. The improvement comprises the cw~ 3 -95~56 reflector ribs each comprising a plurality of connected circular tubes and having an elongated cross-sectional configura~ion, with the elongation being in a direction generally parall.el to the axis of the feed.
cwt ~ - 3a -,'`
~ ~5556 In one embodiment of the invention, the reflector ribs each comprise a plurality of connected circular tubes.
In another embodiment of the invention, the reflector ribs each comprise a tubular conductive member with the cross-sectional configuration of the tube having a major axis in a direction generally parallel to the axis of the feed and having a minor axis generally perpendicular to the major axis. In one form of this embodiment, the reflector ribs each comprise a tubular conductive member having a generally rectangular cross-sectional configuration.
In the illustrative embodiment, the feed includes passive means for providing a relatively rectangular primary beam. The passive means comprise a secondary member carried by the feed for providing a phase shift to shape the primary beam so that it is relatively rectangular A more detailed explanation of the invention is provided in the following description and claims, and is illustrated in the aceompanying drawings.
BRIEF DESCRIPTION OF ThE DGAWlNGS
FIGURE 1 is a perspeetive view of a grid parabolie antenna eonstrueted in aeeordanee with the prineiples of the present invention;
FIGURE 2 is a eross-seetional view thereof, taken along the plane of the line 2-2 of FIGURE l;
FIGURE 3 is an enlarged, broken eross-seetional view, taken along the plane of the line 3-3 of FIGURE 2;
FIGURE 4 is a eross-seetional view similar to FIGURE
3, but showing another form of refleetor ribs;
FIGURE 5 is a eross-seetional view similar to FIGURE
3, but showing a urther form of refleetor ribs;
FIGURE 6 is a eross seetional view similar to FIGURE 3, .. . . . . . ., . _ _ . _ , . ..
"` i.2~S556 but showing an additional form of reflector ribs; and FIGURE 7 is a diagram of a beam pattern of a grid parabolic antenna, showing the beam pattern of a conven-tional grid parabolic antenna in phantom lines and showing, in full lines, the beam pattern of a grid parabolic antenna constructed in accordance with the principles of the present invention.
DETAILED DESCRIPTION OE TIIE
_ ILLUSTRATIVE EMBODIMENT
Referring to the drawings, a grid parabolic antenna 10 is shown therein comprising a circumferential hoop 12 preferably formed of aluminum tubing and a number of spaced reflector ribs 14 preferably formed of aluminum. Each of the reflector ribs has a parabolic contour as illustrated in FIGURE 1 and has its ends connected to hoop 12. As is conventional in grid parabolic antenna designs, the reflector ribs are supportedly connected to a number of metallic straps 16 which are contoured as illustrated in FIGURE 1 and have their ends connected to hoop 12. The assembly is connected to and supported by a mast 18 through A back ring 20 snd a ring back mount as is well-known in the art. A numlber of back braces 22 have their ends connected to back rings 20 and hoop 12.
Spaced reflector ribs 14 each lie in planes that are parallel to each other. Spaeed straps 16~eaeh lie in planes that are parallel to each other and are perpendicular to the planes in which reflector ribs 14 lie. An antenna feed 24 extends from the focus of the parabola formed by the reElector ribs 14 in the manner lllustrated in FIGURES 1 and 2.
Eaeh of the reEleetor ribs 14 has an elongated eross-, _ . , . _ .. _ . . . _ . . .. _ _ .
;1.2~5556 sectional configuration, with the elongation being in a direction that is parallel to the axis of the feed 24.
Referring to FIGURES 2 and 3, for example, it is seen that each reflector rib 14 comprises three aluminum tubes 14a, 14b and 14c connected to each other by solder or other suitable means. Each tube 14_, 14_ and 14c is identical to the others and it can be seen that the tubes are connected so that they lie in a single plane that is parallel to the plane in which the axis of antenna feed 24 lies. In a specific example, although no limitations are intended, in a six-foot diameter parabolic antenna constructed in accordance with the principles of the present invention, each tube 14a has a circular cross-sectional configuration with a 3/4 inch diameter, and the reflector ribs 14 are spaced two inches apart from each other.
By utilizing reflector ribs which each have an elon-gated cross-sectional configuration, with the elongation being in a direction generally parallel to the axis of the feed, the amount of back radiation is reduced substantially.
The amount of back radiation using the elongated reflector ribs is further reduced by attaching passive means to the feed comprising a secondary member carried by the feed for providing a phase shift, to shape the primary beam so it is relatively rectangular. To this end, a wave shaping element 30 is attached to feed 24. Feed 24 and its wave shaping element 30 are supported through a number of cables 32, which extend from the wave shaping element 30 to back ring 20. As ifl conventional, the back end ~not shown) of antenna feed 24 has a coaxial coupler for receiving a coaxial cable.
As illustraced in FIGURE 2 in cross-section, wave shaping element 30 essentially comprises a number of concentric rings, as is well-lcnown in the art, to shape the , . ... .. ,, _ _ " ` lZ~iS~
primary beam so that it is relatively rectangular. Referring to FIGURE 7, which diagrammatically shows the beam over a 360 scale, primary beam 40 is the typical beam from the front of the parabolic antenna without using wave shaping element 30. Using wave shaping element 30, the beam is shaped in a relatively rectangular configuration 42 thus reducing reflector spillover. It has been found that by shaping the beam so that it is relatively rectangular, and also using reflector ribs which have an elongated cross-sectional configuration as illustrated in FIGURES 1-3, the amount of back radiation may be reduced by a factor of 10.
This provides a grid antenna which has substantially no greater back radiation than a solid antenna of the same diameter. In this manner, where a solid antenna may be undesirable a grid antenna may be utilized in compliance with the FCC standard described above.
Reflector ribs 14 may have other cross-sectional configurations, so long as the cross-sectional configuration is elongated in a direction generally parallel to the axis of the feed. For example, in FIGURE 4 each reflector rib 14 comprises a tubular conducti-ve member with the cross-sectional configuration being generally diamond-shape.
The major axis of the diamond is parallel to the axis of feed 24 and the minor axis of the diamond is perpendicular thereto.
Likewise, in FIGURE 5 each reflector rib 14 has a generally rectangular cross-sectional configuration, with the major axis of the rectangle being parallel to the axis of feed 24 while the minor axis of the rectangle is perpendicular thereto.
In FIGURE 6, reflector ribs 14 are tubular with a generally elliptical cross-sectional configuration. As illustrated in FIGURE 6, the major axis of the ellipse is ~.2~35S56 parallel to the axis of feed 24 while the minor axis of the ellipse is perpendicular thereto.
Although antenna 10 has been primarily described as a transmitting antenna, it may also be used as a receiving antenna utilizing the principles of the present invention.
It is seen that a novel grid parabolic antenna has been shown and described which is relatively simple in construction and easy to manufacture, and minimizes the back radiation by utilizing the novel construction.
Although illustrative embodiments of the invention have been shown and described, it is understood that various modifications and substitutions may be made by those skilled in the art without departing from the novel spirit and scope of the present invention.
. , . _ _ . , ... _.. .. ___ ., . . __ .
FIGURE 5 is a eross-seetional view similar to FIGURE
3, but showing a urther form of refleetor ribs;
FIGURE 6 is a eross seetional view similar to FIGURE 3, .. . . . . . ., . _ _ . _ , . ..
"` i.2~S556 but showing an additional form of reflector ribs; and FIGURE 7 is a diagram of a beam pattern of a grid parabolic antenna, showing the beam pattern of a conven-tional grid parabolic antenna in phantom lines and showing, in full lines, the beam pattern of a grid parabolic antenna constructed in accordance with the principles of the present invention.
DETAILED DESCRIPTION OE TIIE
_ ILLUSTRATIVE EMBODIMENT
Referring to the drawings, a grid parabolic antenna 10 is shown therein comprising a circumferential hoop 12 preferably formed of aluminum tubing and a number of spaced reflector ribs 14 preferably formed of aluminum. Each of the reflector ribs has a parabolic contour as illustrated in FIGURE 1 and has its ends connected to hoop 12. As is conventional in grid parabolic antenna designs, the reflector ribs are supportedly connected to a number of metallic straps 16 which are contoured as illustrated in FIGURE 1 and have their ends connected to hoop 12. The assembly is connected to and supported by a mast 18 through A back ring 20 snd a ring back mount as is well-known in the art. A numlber of back braces 22 have their ends connected to back rings 20 and hoop 12.
Spaced reflector ribs 14 each lie in planes that are parallel to each other. Spaeed straps 16~eaeh lie in planes that are parallel to each other and are perpendicular to the planes in which reflector ribs 14 lie. An antenna feed 24 extends from the focus of the parabola formed by the reElector ribs 14 in the manner lllustrated in FIGURES 1 and 2.
Eaeh of the reEleetor ribs 14 has an elongated eross-, _ . , . _ .. _ . . . _ . . .. _ _ .
;1.2~5556 sectional configuration, with the elongation being in a direction that is parallel to the axis of the feed 24.
Referring to FIGURES 2 and 3, for example, it is seen that each reflector rib 14 comprises three aluminum tubes 14a, 14b and 14c connected to each other by solder or other suitable means. Each tube 14_, 14_ and 14c is identical to the others and it can be seen that the tubes are connected so that they lie in a single plane that is parallel to the plane in which the axis of antenna feed 24 lies. In a specific example, although no limitations are intended, in a six-foot diameter parabolic antenna constructed in accordance with the principles of the present invention, each tube 14a has a circular cross-sectional configuration with a 3/4 inch diameter, and the reflector ribs 14 are spaced two inches apart from each other.
By utilizing reflector ribs which each have an elon-gated cross-sectional configuration, with the elongation being in a direction generally parallel to the axis of the feed, the amount of back radiation is reduced substantially.
The amount of back radiation using the elongated reflector ribs is further reduced by attaching passive means to the feed comprising a secondary member carried by the feed for providing a phase shift, to shape the primary beam so it is relatively rectangular. To this end, a wave shaping element 30 is attached to feed 24. Feed 24 and its wave shaping element 30 are supported through a number of cables 32, which extend from the wave shaping element 30 to back ring 20. As ifl conventional, the back end ~not shown) of antenna feed 24 has a coaxial coupler for receiving a coaxial cable.
As illustraced in FIGURE 2 in cross-section, wave shaping element 30 essentially comprises a number of concentric rings, as is well-lcnown in the art, to shape the , . ... .. ,, _ _ " ` lZ~iS~
primary beam so that it is relatively rectangular. Referring to FIGURE 7, which diagrammatically shows the beam over a 360 scale, primary beam 40 is the typical beam from the front of the parabolic antenna without using wave shaping element 30. Using wave shaping element 30, the beam is shaped in a relatively rectangular configuration 42 thus reducing reflector spillover. It has been found that by shaping the beam so that it is relatively rectangular, and also using reflector ribs which have an elongated cross-sectional configuration as illustrated in FIGURES 1-3, the amount of back radiation may be reduced by a factor of 10.
This provides a grid antenna which has substantially no greater back radiation than a solid antenna of the same diameter. In this manner, where a solid antenna may be undesirable a grid antenna may be utilized in compliance with the FCC standard described above.
Reflector ribs 14 may have other cross-sectional configurations, so long as the cross-sectional configuration is elongated in a direction generally parallel to the axis of the feed. For example, in FIGURE 4 each reflector rib 14 comprises a tubular conducti-ve member with the cross-sectional configuration being generally diamond-shape.
The major axis of the diamond is parallel to the axis of feed 24 and the minor axis of the diamond is perpendicular thereto.
Likewise, in FIGURE 5 each reflector rib 14 has a generally rectangular cross-sectional configuration, with the major axis of the rectangle being parallel to the axis of feed 24 while the minor axis of the rectangle is perpendicular thereto.
In FIGURE 6, reflector ribs 14 are tubular with a generally elliptical cross-sectional configuration. As illustrated in FIGURE 6, the major axis of the ellipse is ~.2~35S56 parallel to the axis of feed 24 while the minor axis of the ellipse is perpendicular thereto.
Although antenna 10 has been primarily described as a transmitting antenna, it may also be used as a receiving antenna utilizing the principles of the present invention.
It is seen that a novel grid parabolic antenna has been shown and described which is relatively simple in construction and easy to manufacture, and minimizes the back radiation by utilizing the novel construction.
Although illustrative embodiments of the invention have been shown and described, it is understood that various modifications and substitutions may be made by those skilled in the art without departing from the novel spirit and scope of the present invention.
. , . _ _ . , ... _.. .. ___ ., . . __ .
Claims (7)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. In a grid parabolic antenna formed of a peripheral hoop and a plurality of spaced metallic reflector ribs having a parabolic contour, the reflector ribs being arranged in planes substantially parallel to each other and being connected to the hoop, an antenna feed at the focus of the parabola, the improvement comprising:
said reflector ribs each comprising a plurality of connected circular tubes and having an elongated cross-sectional configuration, the elongation being in a direction generally parallel to the axis of the feed.
said reflector ribs each comprising a plurality of connected circular tubes and having an elongated cross-sectional configuration, the elongation being in a direction generally parallel to the axis of the feed.
2. In a grid parabolic antenna as described in Claim 1, said feed including passive means for providing a relatively rectangular primary beam.
3. In a grid parabolic antenna as described in Claim 2, said passive means comprising a wave shaping element which provides a phase shift.
4. In a grid parabolic antenna as described in Claim 2, said passive means comprising a secondary member carried by the feed for providing a phase shift to shape the primary beam so that it is relatively rectangular.
5. In a grid parabolic antenna formed of a peripheral hoop and a plurality of spaced metallic reflector ribs having a parabolic contour, the reflector ribs being arranged in planes substantially parallel to each other and being connected to the hoop, an antenna feed at the focus of the parabola, the improvement comprising:
said reflector ribs each having an elongated cross-sectional configuration, the elongation being in a direction generally parallel to the axis of the feed;
said feed including passive means for providing A relatively rectangular primary beam.
said reflector ribs each having an elongated cross-sectional configuration, the elongation being in a direction generally parallel to the axis of the feed;
said feed including passive means for providing A relatively rectangular primary beam.
6. In a grid parabolic antenna as described in Claim 5, said reflector ribs each comprising a tubular conductive member with the cross-sectional configuration of the tube having a major axis in a direction generally parallel to the axis of the feed and having a minor axis generally perpendicular to the major axis.
7. In a grid parabolic antenna as described in Claim 6, said passive means comprising a secondary member carried by the feed for providing a phase shift to shape the primary beam so that it is relatively rectangular.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| US06/461,143 US4801946A (en) | 1983-01-26 | 1983-01-26 | Grid antenna |
| US461,143 | 1983-01-26 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1205556A true CA1205556A (en) | 1986-06-03 |
Family
ID=23831393
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA000446113A Expired CA1205556A (en) | 1983-01-26 | 1984-01-26 | Grid antenna |
Country Status (6)
| Country | Link |
|---|---|
| US (1) | US4801946A (en) |
| JP (1) | JPS59140702A (en) |
| CA (1) | CA1205556A (en) |
| DE (1) | DE3402489A1 (en) |
| GB (1) | GB2135132B (en) |
| IT (1) | IT1178098B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9057536B2 (en) | 2008-06-06 | 2015-06-16 | Sunrise Csp Pty Limited | Solar thermal collectors |
Families Citing this family (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5258767A (en) * | 1989-03-14 | 1993-11-02 | Kokusai Denshin Denwa Co., Ltd. | Antenna system for shaped beam |
| GB2242072B (en) * | 1990-03-16 | 1993-12-08 | C S Antennas Ltd | Reflector antenna |
| GB9125401D0 (en) * | 1991-11-29 | 1992-01-29 | Concentric Pressed Products Lt | Reflector antennae |
| US5291212A (en) * | 1992-09-01 | 1994-03-01 | Andrew Corporation | Grid-type paraboloidal microwave antenna |
| JPH0786829A (en) * | 1993-09-17 | 1995-03-31 | Nec Corp | Reflector antenna |
| USD382566S (en) * | 1996-05-07 | 1997-08-19 | Espey Mfg. & Electronics Corp. | Dual dipole antenna |
| US5894290A (en) * | 1996-10-09 | 1999-04-13 | Espey Mfg. & Electronics Corp. | Parabolic rod antenna |
| USD418841S (en) * | 1999-03-01 | 2000-01-11 | Espey Mfg & Electronics Corp. | Parabolic slat antenna |
| US6188370B1 (en) * | 1999-06-24 | 2001-02-13 | California Amplifier, Inc. | Grid antennas and methods with efficient grid spacing |
| US6512495B1 (en) * | 2001-08-28 | 2003-01-28 | Qualcomm, Inc. | Concave reflector with phase shifted and selectively focused output energy |
| FR2850796A1 (en) * | 2003-02-04 | 2004-08-06 | Cit Alcatel | SECONDARY REFLECTOR FOR CASSEGRAIN-TYPE MICROWAVE ANTENNA |
| WO2013031396A1 (en) * | 2011-08-26 | 2013-03-07 | 日本電気株式会社 | Antenna device |
| BR202014013528Y1 (en) * | 2014-06-04 | 2018-11-06 | João Alexandre De Abreu | satellite dish with self-structuring reflector |
| CN108511920A (en) * | 2018-02-09 | 2018-09-07 | 上海复合材料科技有限公司 | Covering reinforced structure antenna reflector and preparation method thereof |
| USD971900S1 (en) | 2019-06-03 | 2022-12-06 | Space Exploration Technologies Corp. | Antenna apparatus |
| USD976242S1 (en) | 2019-06-03 | 2023-01-24 | Space Exploration Technologies Corp. | Antenna apparatus |
| USD971192S1 (en) | 2019-06-03 | 2022-11-29 | Space Exploration Technologies Corp. | Antenna apparatus |
Family Cites Families (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB817170A (en) * | 1955-12-23 | 1959-07-22 | Gen Electric Co Ltd | Improvements in or relating to passive elements for modifying the phase-front of electromagnetic waves |
| GB595062A (en) * | 1943-01-27 | 1947-11-26 | Marconi Wireless Telegraph Co | Improvements in radio-systems, and reflectors therefor |
| US2423648A (en) * | 1943-01-27 | 1947-07-08 | Rca Corp | Antenna |
| US2530098A (en) * | 1945-05-03 | 1950-11-14 | Lester C Van Atta | Antenna |
| US2703842A (en) * | 1950-03-08 | 1955-03-08 | Willard D Lewis | Radar reflector |
| NL211504A (en) * | 1955-10-18 | |||
| DE1002411B (en) * | 1955-10-18 | 1957-02-14 | Siemens Ag Albis | Reflector antenna for microwaves |
| US2850735A (en) * | 1956-06-19 | 1958-09-02 | Edward F Harris | Parabolic antenna structure |
| US3178713A (en) * | 1961-03-08 | 1965-04-13 | Andrew Corp | Parabolic antenna formed of curved spaced rods |
| US3274603A (en) * | 1963-04-03 | 1966-09-20 | Control Data Corp | Wide angle horn feed closely spaced to main reflector |
| US3553707A (en) * | 1967-05-25 | 1971-01-05 | Andrew Corp | Wide-beam horn feed for parabolic antennas |
| US3886557A (en) * | 1973-11-28 | 1975-05-27 | Texas Instruments Inc | Radar antenna and method of fabricating same |
| GB1457907A (en) * | 1974-02-27 | 1976-12-08 | Terma Elektronisk Ind As | Microwave antennas |
| US4168504A (en) * | 1978-01-27 | 1979-09-18 | E-Systems, Inc. | Multimode dual frequency antenna feed horn |
| JPS556178U (en) * | 1978-06-28 | 1980-01-16 | ||
| DE3027095A1 (en) * | 1979-11-19 | 1982-12-02 | The Marconi Co. Ltd., Chelmsford, Essex | Aerial with large surface area parabolic reflector - consists of parallel carbon fibre reinforced plastic slats fed from horns, for marine radar |
| US4405928A (en) * | 1980-03-17 | 1983-09-20 | Harris Corporation | Wind load reduction in tower mounted broadcast antennas |
| US4414516A (en) * | 1981-11-18 | 1983-11-08 | Chaparral Communications, Inc. | Polarized signal receiver system |
| US4477816A (en) * | 1982-07-14 | 1984-10-16 | International Telephone & Telegraph Corporation | Corrugated antenna feed horn with means for radiation pattern control |
-
1983
- 1983-01-26 US US06/461,143 patent/US4801946A/en not_active Expired - Fee Related
-
1984
- 1984-01-17 GB GB08401164A patent/GB2135132B/en not_active Expired
- 1984-01-25 IT IT47592/84A patent/IT1178098B/en active
- 1984-01-25 DE DE19843402489 patent/DE3402489A1/en not_active Ceased
- 1984-01-25 JP JP59011795A patent/JPS59140702A/en active Pending
- 1984-01-26 CA CA000446113A patent/CA1205556A/en not_active Expired
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9057536B2 (en) | 2008-06-06 | 2015-06-16 | Sunrise Csp Pty Limited | Solar thermal collectors |
Also Published As
| Publication number | Publication date |
|---|---|
| US4801946A (en) | 1989-01-31 |
| JPS59140702A (en) | 1984-08-13 |
| DE3402489A1 (en) | 1984-07-26 |
| IT8447592A0 (en) | 1984-01-25 |
| GB2135132A (en) | 1984-08-22 |
| GB2135132B (en) | 1986-07-02 |
| GB8401164D0 (en) | 1984-02-22 |
| IT1178098B (en) | 1987-09-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CA1205556A (en) | Grid antenna | |
| US4343005A (en) | Microwave antenna system having enhanced band width and reduced cross-polarization | |
| US5170176A (en) | Quadrifilar helix antenna | |
| US5113197A (en) | Conformal aperture feed array for a multiple beam antenna | |
| US4673945A (en) | Backfire antenna feeding | |
| US4626863A (en) | Low side lobe Gregorian antenna | |
| DE69834968T2 (en) | Dual reflector microwave antenna | |
| US6483471B1 (en) | Combination linearly polarized and quadrifilar antenna | |
| WO1994022180A1 (en) | Stacked biconical omnidirectional antenna | |
| US6995727B2 (en) | Reflector antenna feed | |
| JPS6341443B2 (en) | ||
| US4423422A (en) | Diagonal-conical horn-reflector antenna | |
| CN112599980B (en) | Dual-band multimode combined feed source loudspeaker | |
| DE2319731A1 (en) | ECCENTRIC CASSEGRAIN ANTENNA | |
| US4249183A (en) | Periscope arrangement with protection against parasitic radiation | |
| US5204688A (en) | Omnidirectional antenna notably for the emission of radio or television broadcasting signals in the decimetric waveband, and radiating system formed by a grouping of these antennas | |
| US3706999A (en) | Cassegraninian antenna having limited spillover energy | |
| CN213905606U (en) | Dual-band multi-mode combined feed source loudspeaker | |
| EP0155761A1 (en) | Planar-parabolic reflector antenna with recessed feed horn | |
| US4051481A (en) | Helical band antenna | |
| GB2059684A (en) | Directional antenna | |
| JP3334134B2 (en) | Helical antenna system | |
| US3235868A (en) | Zig-zag uhf antenna with four square diamond-shaped portions and quarter wave stubs | |
| JPS6128403Y2 (en) | ||
| EP0136817A1 (en) | Low side lobe gregorian antenna |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| MKEX | Expiry |